That One Adventure Thor and Loki Swear Never Happened
by isis uf
Summary: For once, it's one hundred percent not Loki's fault. Mostly. If you look at it the right way, anyhow. (Or, that one where Loki and Thor accidentally swap bodies and awkwardness happens) [Sif/Loki]
1. Chapter 1

**That One Adventure Thor and Loki Swear Never Happened**

**Rating** - M

**Tags** - Sif/Loki, kind of but not really Sif/Thor, Loki & Thor, trope bingo, cliches, body swap, accidental powers, humor, angst, nudity, Thor might be scarred for life, brotherhood, unhealthy sibling rivalry, pre-canon, artistic license with Norse mythology, why is this so long?, this was really meant to be a one-shot, bad attempts at using Old Norse names for things

**Summary** - For once, it's one hundred percent not Loki's fault. Mostly. If you look at it the right way, anyhow. (Or, that one where Loki and Thor accidentally swap bodies and awkwardness happens)

**Author's Note** - This will be 5-6 chapters, which is 4-5 chapters longer than I had originally expected. The second chapter is nearly done. I hope to have this finished in its entirety relatively quickly (within a few weeks). This is the second challenge in my Trope Bingo Blackout attempt (filling both the "body swap" and "accidental powers" squares).

It's Thor's fault.

That's what Loki will maintain later, anyhow, and it's not as though Thor will argue it because that would mean acknowledging the whole thing happened in the first place. And frankly? That's not something Thor will do.

It starts in the palace on Alfheim because most of their adventures begin in seemingly innocuous places. It's proof that Loki can start trouble anywhere, really, even if this time completely isn't his fault.

"I cannot imagine this to be a good idea," says Loki, but he doesn't break his stride next to Thor because - good idea or not - it's certainly mischief and so that means it isn't precisely a _bad_ idea either.

Okay, so maybe it's a little his fault, too.

"You worry too much, brother," Thor says, which in itself should be proof enough that Thor is wholly focused on his task at hand and not thinking before speaking.

It is a silly thing, to risk angering the Ljósálfar _and_ their father, for a glimpse of some long ago locked away treasures. Nevermind the dangers of the treasures themselves.

"Or perhaps it is that your head is too full of glory and adventure to worry at all," Loki counters.

"You tell me the elves have the great and cursed sword Tyrfing. You tell me you know where it sits and yet you expect me to let such a thing lie without seeking it out?" Thor questions. "I presume you to know me far better than that, brother."

"Surely even you must realize you cannot unsheath it," Loki asks, eyeing his brother warily. "If you intend to, I must decline to follow along on this little jaunt as the sword has a rather well-known history of fratricide."

"Nay," Thor assures him. "It pains me to say as much, but I shall not wield the thrice-cursed bloodied blade. Though a sword which shall not rest until it has quenched its thirst for blood and dispatched a soul to Helheim or Valhalla ought not lay forgotten in some treasure trove. She ought sing upon a field of battle 'til such time as Ragnarök meets its dusk."

_Count on Thor to wax poetic about death and war and the end of days_, Loki thinks dryly.

The halls of the Elven castle are long and winding and have no shortage of guards, but it is a small thing for Loki to distract them. An illusion here, an errant shadow there, a clamor of noise down the hall, a snuffed out candle at an opportune moment. It's not even a challenge really. The only real danger is that Thor's bombastic voice will echo off the smooth stone walls and gain more attention than Loki's spells, but even the God of Thunder can be stealthy when its required.

Loki likes to think its his influence.

"Your proficiency with the seiðr grows stronger with each passing century," Thor compliments in a subdued tone. "I admit, understanding of it eludes me even at the most basic level, and yet I can admire that you have developed it into a most useful skill."

If the compliment throws Loki at all, he doesn't show it.

"Yes, well, battles are not only won by muscles and steel, are they?" Loki asks.

"Nay," Thor agrees good-naturedly. "And yet I will take the might of a hammer over the bending of shadows in any brawl. However, you cope quite finely by playing to your strengths in order to balance out what skills you are ill-equipped with. It is most impressive how you have managed in spite of your shortcomings."

The backhanded compliment is one of Thor's worst and Loki smiles thinly through gritted teeth because it is that or stab his brother in the gut to make a point and Loki is not terribly fond of the road that might set him upon. If he going to start Ragnarök it will not be because _Thor_ made him do it.

"We are here," he says instead, twisting the lock on the vault doors with his magic and soundlessly throwing it wide as if to make a point.

To be fair, it's a valid point to make. Thor's mighty hammer might have been able to pound the blasted door open, but it most assuredly would have caused a racket that would have brought the Elven guards running and wouldn't _that_ be a fine diplomatic mess.

The room is dewy and bright, but with no obvious light source, and filled with treasures, each on pedestals of their own and spaced just a few paces apart from each other. Directly in the middle of the room sits the obvious point of this entire expedition.

Thor's eyes widen, much as they had the first time he'd been given a horse of his own, and he takes a few trance-like steps toward the sword until he's close enough that he could easily grasp the thing if he chose to. Given the weapon's history, Loki rather wishes he'd back up a few steps, for safety's sake.

Even sheathed, it is clearly a lovely thing. Legend tells that it is of Dwarven craft and Loki can immediately see the truth of that, even from a few paces away. The hilt is gold and very fine, with brutal designs of battle carved into it. Though gold itself is a rather delicate metal, there are no nicks in it, nor any damage to its scabbard. Were it not for the magic the weapon reeked of, he'd have thought the blade had never been used.

"Can you imagine such a thing in the hands of Fandral or Lady Sif?" Thor asks in wonderment.

Loki gives a sidelong glance to his brother.

"Lady Sif needs no enchantments upon her weapons to banish souls to Hela's realm," Loki replies smoothly.

"True enough," Thor says boisterously, clapping his brother on the back. "In fairness, there are times she needs not weapons at all, for she is deadly without her steel as well."

Yes. Loki is well aware of this.

"I wish that I could but glimpse upon the blade itself," Thor says longingly and a tremor of foreboding works its way down Loki's back.

"And if you could glimpse upon it, then you would wish only to weigh and balance it. And if you could weigh and balance it, then you would wish only to spar with it. And if you could spar with it, then you would wish only to bring it along on a small skirmish. Need I go on, brother, or have I made my point?" Loki drawls.

"Nay," Thor sighs pitifully. "Your point is made and there is truth in it."

"Tell no one," Loki smiles. "I've a reputation, after all."

Thor snorts, sounding more like an amused horse than a Prince of Asgard to Loki's ears, and smiles broadly in return.

"I fear most would sooner believe me a liar than call you a truth-teller, Loki," he says.

Loki smiles back. There's something pleasant in knowing one's reputation is secure.

"Come, we ought-" Loki starts, but is cut off as Thor turns and his arm hits a nearby dais holding some other treasure.

They had been so focused on the one artifact they knew of in the room, that they'd all but forgotten the hidden dangers of the ones around it.

In hindsight, this will be where things went very wrong.

It's always why it was all Thor's fault.

Both Thor and Loki can see that the intricate and _delicate_ looking cup perched atop the pedestal is going to fall. Thor is closer and makes an immediate grab for the thing. A strange sort of glaze works its way across his eyes as as he touches it and the God of Lightning's fingers go slack against the chalice as his eyes roll back into his head and he starts to collapse. Loki has but a moment to make a choice whether to try and save the cup or halt his brother's fall.

He makes the obvious choice and grabs for the cup. Thor's head has suffered far worse than a smack against a stone floor.

But then, with the cup clenched in his hand, the strangest feeling washes over Loki, like his soul or his magic is unanchored. He feels adrift, as though the tides might be washing him over the edge of Asgard's oceans and into the abyss.

_Well… isn't this just perfect_, is the last thing Loki thinks before losing consciousness.


	2. Chapter 2

The very first thing Loki realizes upon waking up is that Thor's hand is in his face. Or, rather, _on_ his face. Large, meaty fingers are partially blocking his vision. He groans and goes to swat the offending digits away but that's when things get weird. Or weirder, anyhow. He and Thor being felled by an archaic cup is strange all on its own.

Thor's hand moves, but his own hand doesn't respond like he expects and he finds his body twisting oddly as if its overreacting to his own commands. What happens next will go down as one of the most surprising and horrifying moments of his extremely long existence.

He sees himself laying unconscious.

Possibilities shoot through his mind like lightning bolts. Is he staring at a double? No. Is he dead? Unlikely as this does not appear to be Helheim. Is he having some sort of out-of-body experience? He wouldn't discount this readily except for the memory of Thor's damned fingers splayed across his face.

Wait.

Thor.

He looks around but doesn't spy his burly brother, which is rather remarkable because he's somewhat hard to miss. Then he looks down at his arm, his hands, and finds that while they are familiar, they most certainly are not his own.

"Brother?" He calls out.

But it's not his own voice he hears doing the calling. No. It's Thor's.

"Thor!" He says more demandingly. "Wake _up_!"

As he expected - but had greatly wished would not be the case - his own form rouses into wakefulness. It takes a few moments, but eventually his own pale eyes switch from blinking at him in disorientation to broadening in surprise.

"What sorcery is this?" Thor asks in Loki's voice, with more confusion in his tone than has ever been expressed in Loki's voice in the entirety of his eleven-hundred years.

"None of my doing, brother," Loki assures him.

"That is most unfortunate, as I had hoped this was but an elaborate prank," Thor sighs mournfully.

"It would be an excellent one," Loki acknowledges.

"Have you the ability to reverse this magic?" Thor asks, his eyes lighting up with hope at the thought.

Loki digs for his magic, seeks to tug at the strands of power that he has called upon for centuries to do his bidding. He finds nothing.

A deep sense of horror trickles down his spine as realization sets in. He is in Thor's body and Thor has no connection to the threads of seiðr that surround them all. It leaves him feeling helpless, vulnerable in a way he's not been since he first cast forth a double of himself in early adolescence.

"I fear that power resides with you," he simply says.

Thor's eyes widen at that, more expression showing on the mask of Loki's face than has likely happened ever before. A look of concentration then takes over his features and it takes Loki a moment to realize precisely what his brother is doing. By then, there is a spark on Thor's fingertips, an angry and uncontrolled thing that zips off sideways and scarcely misses some treasure before fizzling into nothingness.

"_Are you mad_?" Loki hisses.

"I thought to fix this," Thor says with a shrug.

"You've had magic for all of five minutes and you thought you could just bend it to your will? Not everything can be _beaten_ into submission, Thor," Loki says angrily.

"It seemed worth a try," Thor says evenly.

"It was not," Loki assures him.

His head is pounding and - not for the first time since waking up - he wishes rather fiercely that he'd chosen to make a grab for Thor rather than the chalice. The impact of the stone floor on Thor's thick skull had rather unpleasant and unexpectedly personal after-effects. And, the chalice… had he not grabbed for the chalice…

He looks around for the blasted cup now and finds it intact, just an arm's length away on his left. What a powerful artifact it must be. How much magic must be imbued in its small form. He reaches for it but halts as Thor makes a little strangled noise.

"Is that wise, brother?" Thor questions. "If it indeed caused this predicament, as seems likely, who knows what other powers it might have."

"Or it might right us," Loki counters. "Have you another idea?"

Thor thinks a moment before sighing, drooping his shoulders in defeat.

"Nay, for we cannot confess the truth of our situation without also confessing to having broken into the Elven treasure room," Thor acknowledges. "I know not what our punishment would be for such a thing. I dare not imagine it."

"On that, we most assuredly agree," Loki tells him.

He braces himself before grabbing the cup, half expecting to pass out again but it does not happen. Indeed, it's all a bit of a let down, for nothing happens at all. The little huff of disappointment Thor lets out is more than proof enough that he too had been expecting something - anything - to happen.

"Perhaps if you held it too?" Loki suggests, though his hopes are not high.

Thor has a stupidly innocent and insanely hopeful look on Loki's face and Loki hates it on principle because he's never, ever been that naive and, if he was, he's certainly never had to _look _at it before.

Thor grabs for the cup. Again, nothing happens.

The look of disappointment Thor wears would have been unbearable on his own face; it's ten times worse wearing Loki's visage as a mask. Loki looks terrible when he pouts.

"What now, brother?" Thor asks.

"It's possible that simply time and distance will dissolve the spell's effects. Such magic would be difficult to sustain," Loki tells him. "But barring that, I'll need to research this cup, see if I cannot find more about its intent."

"You mean… for now, we must act as though we are each other?" Thor asks bewildered.

Loki wonders if Thor _has_ an expression beyond bewilderment, hopefulness, bravado and despondency. He hopes so, for if not there is no way anyone will believe him to be Loki for any length of time.

"For now," Loki agrees, "it appears we haven't a choice."

Escaping detection as they leave the treasure room is rather harder than breaking in was, for they haven't Loki's magic to provide distraction this time. In truth, it's mostly luck that allows them to put enough distance between themselves and the Elven artifacts to avoid suspicion before they run into their father.

"Father!" Thor says in surprise and Loki suppresses an instinctive eye-roll.

Apparently, they're going to have to discuss the finer details of impersonating each other.

Odin looks strangely at the both of them and for a moment Loki wonders if his father can see precisely what's happened. But the moment passes and Loki lets out a slow breath of relief as Odin addresses them both.

"I've been looking for you. Our trip must be cut short, unfortunately," Odin tells them both. "There are reports of mountain trolls raiding our villages in the north. I've ordered Sif and The Warriors Three dispatched to deal with the incursion, but there are villagers taking refuge at court and our presence there is necessary."

Loki watches as disappointment rolls over his own face; Thor is clearly mournful that he's missed out on a chance for glory. Loki, too, is mournful, but for an entirely different reason. Their best chance at finding information on the cup is in the library _here_ and if simple time and distance do not undo the threads of the spell, it will be difficult to engineer a reason to return to Alfheim.

"I would volunteer to join the others in the north," Loki says, both because dealing with refugees doesn't sound like fun and it sounds like something Thor might say. "If you would grant me leave to do so, father."

"No," Odin says with a shake of his head and a heavy but affectionate hand on Loki's shoulder. "The beasts will be dispatched handily by your friends. Your presence would be better served as a boon to those seeking the safety of the palace."

"When are we to leave?" Thor asks.

"Presently," Odin responds.

Loki hesitates and looks to Thor, finding him wearing a twin face of concern. Hiding that they are not themselves would have been difficult enough _here_, where they are not familiar to many. Hiding what has happened at _home_, where the halls are filled with people they've known for a millennia… that will be another matter entirely.

"Is there a problem?" Odin asks shrewdly.

"Mountain trolls, apparently," Loki replies, wishing he could take back the dry sarcasm if not the words themselves nearly instantly.

"Let us away, then," Odin says after watching them with a narrowed eye for a moment, but - though their father clearly cannot discern _what_ is off about his sons - Loki is quite certain that the king's eye sees more than they would like.

_Yes… surely this will go swimmingly. They will convince everyone quite handily that they are each other and have this fixed in no time with no one ever being the wiser_, Loki thinks to himself as they walk outside and Odin calls down for the bifrost.

As the familiar pull of the bifrost tugs them back to Asgard, he wonders if Thor is capable of his amount of sarcasm.

He doubts it.

They're doomed.


	3. Chapter 3

Arriving back in Asgard, the first thing Thor realizes is that Heimdall - of course - already knows everything. For a moment, he thinks the giant guardian will tell Odin and Thor groans inwardly at the thought. But, the watchman instead looks to Thor a gives a small shake of his head with the thinnest of smiles on his lips.

Thor fears nothing. It's not in his nature. But, if he were so inclined, he might find Heimdall somewhat terrifying. There's something… off-putting about a man who sees _everything_.

"How goes the battle to the north?" Odin asks immediately.

"I see great victories in the making," Heimdall tells him.

"Good," Odin responds crisply.

And with that they head back to the palace.

It's more full than usual, certainly, but not excessively so. There are perhaps two small villages worth of temporary residents. Those not injured and being tended to by Eir and Frigga are eating in the great hall, telling stories of the trolls that seemed to be growing by the second, as tales of trial and strife are wont to do.

First the trolls are ten feet tall, but later Thor hears they are nearer to twenty. At the start there are five, but by late afternoon it's five dozen. Thor has spent enough centuries with The Warriors Three to know the truth lies closer to earlier numbers, but he still longs to be in the thick of fighting. Even in this unfamiliar form.

He and Loki stay near each other the whole afternoon because it seems wise to keep an eye on each other and because they really ought to talk more, since this blasted spell has not released its hold upon them. He had greatly hoped they would somehow arrive in Asgard back in their own bodies, but then he'd also hoped both of them grasping the cup would reverse its spell as well. Such hopes, it seemed, were in vain.

It's after supper before Loki manages to pull him aside, away from the watchful eyes of court and the northerners. They have had a tiring day, but Thor suspects its maintaining this rouse itself that's more exhausting than anything.

"I'll need to try and find information about the chalice in the library," Loki says straight away.

"Will that not look strange, brother?" Thor asks. "For it is not often I am seen hunched over a _book_."

Loki smirks at that and it looks completely out of place on Thor's face.

"Are you proposing _you_ ought look through the books for some reference to the cup, instead of me?" Loki asks loftily. "Can you even _read_ Old Elvish?"

"Some…" Thor says a bit defensively.

"A tavern menu doesn't count," Loki drawls.

"Then what shall I do?" Thor asks.

If he says it a little petulantly, he feels it's entitled in this situation.

"Keep to yourself," Loki tells him. "Impersonating me is simple enough."

Thor snorts by way of response, which in itself is proof enough that he won't find impersonating Loki to be a simple thing.

"I like this not," Thor says after a moment. "It's uncomfortably warm, wearing your skin, and something itches in my veins that I find most annoying."

Loki hesitates at that and surveys his brother a moment before responding.

"The itching feeling is the magic in your blood wanting to out," Loki tells him finally.

"You feel like this _all_ the time?" Thor questions, stunned.

"Of course not," Loki counters, looking at Thor as though he's mad. "I _use_ my magic."

"Is there _nothing_ I can do about it?" Thor asks in a tone that is nearly a whine; Loki has never hated the sound of his own voice before this moment.

"When you're alone in your room, try summoning a ball of light," Loki tells him. "It's the simplest magic I know of and you're unlikely to accidentally blow up the castle or summon a bilgesnipe to the throne room."

"You can summon a bilgesnipe?" Thor asks with undisguised interest and Loki rolls Thor's eyes in response.

"Of course that's the part you focused upon."

Thor's a little disappointed by his brother's response and he's poor at hiding it, but the shake of Loki's head is somehow both judgemental and affectionate. It's a common look for Loki but it _does_ look strange on Thor's face.

"I shall heed your advice," Thor tells his brother, "but we shall discuss your ability to summon great beasts further once this… misadventure is well behind us."

"Your interest in parlor tricks and disinterest in actual magic of consequence is mind boggling," Loki replies dryly, but Thor knows his brother is secretly pleased at his interest in anything magical he does.

"I shall leave you to your research then," Thor says in a tone that sounds annoyingly like a command and clapping Loki on the back before moving to walk down the hall.

"Where is it precisely that you think you are going?" Loki asks suddenly.

"I retire to my room. As you suggested," Thor replies in confusion.

Loki pinches the bridge of his nose - which is startlingly broader than he's used to - and shakes his head in exasperation.

"Thor… you're _me_. Remember?" Loki asks, sounding put out that he has to explain this. "For the time being, we'll need to switch rooms lest the servants and guards grow suspicious and poison the halls with their gossiping tongues."

Understanding dawns and Thor nods with undue seriousness.

"Of course. Of course, you are correct," he replies with a chuckle. "I'd have quite the challenge finding garments to fit your frame in mine own wardrobe, too."

Loki tries not to grit his teeth in response before realizing they aren't _his_ teeth so he really needn't worry about them and grits them out of spite.

"Just… try not to break anything while you're there, would you?" Loki requests, giving up on the rest of whatever her might be inclined to say as he points down the correct hall toward his rooms.

"Not to worry," Thor tells him, smiling broadly. "I shall treat everything as if it were my own."

"That would actually be my concern," Loki replies, but Thor just laughs in response and continues on his way.

Loki's rooms aren't terribly far from his own, but Thor has only rarely visited them. Loki has not, historically, welcomed intrusion upon his solitude. If he wants for company, he seeks it out, if only to stand half in the shadows and make sly comments until Thor and the others draw him in. He is a strange one, Loki, seemingly simultaneously craving acceptance and believing himself above those in his company. In more than a millennia, Thor has not yet figured his brother out, cannot claim to understand him, yet he loves him all the same.

Thor is not surprised, upon entering Loki's sitting area and then the bedroom, to find that everything is rather meticulously organized. It might seem contradictory for someone oft referred to as the God of Chaos to be a bit of a neat freak, but it makes sense with what Thor knows of his brother and his controlled, calculating nature. It is only _other_ people's lives in which Loki loves to sow disorder, not his own.

Thor is about to heed Loki's advice and try to summon up a ball of light - though, frankly, he's not sure precisely _how_ he's meant to do that - when something else draws his attention.

Or rather someone.

The door to Loki's bathroom is opened just a crack and from within Thor can hear the unmistakable sounds of someone in his brother's bath.

In hindsight, Thor will realize he ought have left straight away. He will realize that this, too, is really his fault. Or, he would if he were ever to acknowledge this whole thing happened. Which he won't.

It is instinct and a warrior's nature that leads him to enter his brother's bathroom and discover who the intruder might be, but he is ill-prepared for the sight that greets him.

Sprawled ever-so-comfortably in Loki's bathtub, with pert breasts cresting above the milky water and one leg propped upon the edge of the tub, is Sif.

Thor freezes.

For an instant he actually considers telling her she's mistakenly gone to the wrong room and that her quarters are down near the training yards because that is the only explanation that makes sense in his completely befuddled brain at the moment. Then she turns to look at him and there is a sly, coy smile on her face as she openly appraises his body. _Loki's body_, he corrects himself immediately, for Sif has surely never looked at him like _that_. Though, to be fair, five minutes ago he'd have said she'd never looked at Loki like that either. Apparently he was wrong. About a lot.

"Welcome back, my prince," she says.

It's words she's literally said a thousand times before - both to him and to Loki - but the tone… the _tone_… was something else entirely.

"What are you doing here?" He asks before his brain starts working.

There's an unreadable quirk of her eyebrow at that and Thor realizes he's even more out of his depth than he thought. Not only has he been blindsided by this battle, but he apparently is missing crucial intel regarding his adversary.

"It was an exceedingly short skirmish," she tells him. "There were but three trolls and Hogun took two of the kills. My glaive barely saw blood. It left me most… unsatisfied."

"And so you came here…" Thor leads her.

"And so I came _here_," she says, rising out of the water, "for want of _satisfaction_."

Thor nearly chokes on his tongue.

He's seen Sif nude before. Of course he has. They're warriors and they have dressed each others wounds for centuries, rid themselves of gore and grime in forest streams and mountain lakes. But he has never seen her like _this_. She is a warrior and she is his friend and this absolutely does not fit.

If his groin tightens and a bolt of want shoots through him at the sight of her naked and wet and suggestive, he tells himself it's simply because he's in Loki's body, which is _apparently_ used to such feelings for Sif. He will cling firmly to that notion until Ragnarök comes.

"Are you alright, Loki?" She asks, concern evident in her voice as she towels off her hair but does nothing to conceal her body.

"Of course," he says. "Why wouldn't I be?"

He's trying to sound lofty and unaffected and Loki-like before realizing that he has no idea what Sif and Loki are like in private but it's probably not lofty and clearly not unaffected.

"What have you been up to?" She probes, finally, _mercifully_ reaching for a robe.

"Ah. That would be telling," he replies and tries to smirk.

It's something Loki would say. It's something Loki _has_ said many, many times.

Sif chuckles lowly and takes a few steps, wet footprints trailing across the stone floor to stop right in front of him. There's a smile on her face, a deceptive softness about her, right up until the instant where there's not.

Really he should have seen this coming. He'd been doing a _terrible_ job masquerading as his brother and Sif is very observant.

There is a snarl curling her lip and the bite of a dagger at his throat and fire in her eyes enough that he ought burn from it.

"Who are you and what have you done with the prince?" She demands.

_Ah, yes,_ he thinks with an odd amount of relief given the circumstances, _there's the Sif I know_.


	4. Chapter 4

As it happens, Loki never makes it to the library that night, but not for lack for trying. While people tend to give the trickster prince a wide berth, Thor is approachable and amiable and people flock to him. Loki finds himself besieged by friendship and kindness.

It's incredibly annoying.

One of the northerners finds him in the hall and fawns over a campaign Thor, Sif and the Warriors Three undertook that saved his fields some centuries before (boring). Four warriors that Loki never bothered to learn the names of invite him out for ale and wenching (_classy_). And the Svensdottir twins gigglingly invite him to visit their room tonight because - apparently - last time was wonderful.

Lovely.

Loki declines and inwardly questions his brother's taste in woman. The Svensdottir twins are simpering girls who pose no challenge whatsoever. Where is the fun in that?

The library is but two turns of the hall away and Loki actually thinks he shall finally make it there, albeit far later than he'd intended, when Odin rounds the corner in front of him. His footsteps stutter at the sight of his father wearing a warm, easy smile and directing it at _him_. His father loves him, surely, but there has always been a sense of reservation in their interactions that Loki has never been able to make sense of. And this look now, this look reserved for Thor, would be both heart-warming and heart-wrenching if he were prone to acknowledge such sentimentality.

"What brings you to this part of the castle so late this eve, my son?" Odin asks.

Loki cannot confess to his true aims - they would be far too suspect - but he is ever quick-thinking and sharp-minded and it is a small thing to come up with a suitable response.

"While I much enjoy our time on other realms, I find my bones longed for the Asgard's familiar halls. I merely wander," he replies.

Odin nods thoughtfully and places a warm, heavy hand upon his son's shoulder in affection and solidarity.

"Shall we wander together then?" He asks.

Even if he could find reason to deny Odin this, Loki does not have the will to forego an opportunity for such amiable companionship with his father. He craves it and yet he resents it because the very smile on Odin's lips, the affectionate hand on his shoulder is stolen. This is not his. And yet, he will take it. And he will treasure it. And he will despise it. And envy and hatred will coil in his gut for how much wants this for himself.

"Have you thought more upon the matter we discussed before we left for Alfheim?" Odin asks as they fall into step with each other.

"I have," Loki replies, wary of how this conversation will go.

"And what further thoughts have you had?" Odin asks.

It's terrible wording and Loki answers the only way he really can.

"I find my opinion on the matter has not changed," he says smoothly.

A heavy huff of frustration passes Odin's lips and the king shakes his head in disappointment or disbelief. It's momentarily somewhat heartening to see that Thor - precious, perfect Thor - can evoke this reaction, too.

"I had thought you would be agreeable, truth be told," Odin tells him.

"And why is that?" Loki questions, still searching for footing in this conversation.

Odin sighs at this and thinks too long upon his answer for Loki's liking.

"I wonder… can you imagine what my rule might be like without your mother?" He finally asks.

Loki furrows Thor's brow as he looks to his father. It sounds like a subject change, but Loki knows it isn't and the direction this conversation has taken is making him wary.

"I cannot," he says truthfully.

"The burdens of kingship are many," Odin says gravely as they make their way outside to Frigga's gardens and continue their walk. "And it is vital to have someone at your side to share in them. Your mother is not only my wife, not only a smiling face to greet soldiers home from war. She is my confidant, my guidance, my staunchest ally and my most ardent voice in contention."

Loki suddenly wishes, ever so fervently, that he were anywhere but here, having any conversation but this.

"Mother is singularly suited to the task," Loki finally grits out.

"She balances me well," Odin admits. "I can only hope to see you as well matched by the time such burdens of the realm fall to you."

Loki wants to laugh. Bitterly. Sourly. Madly. But he cannot, so he clenches his jaw so tightly that it_ hurts_ and he finds it somewhat amazing that Thor's teeth don't crack from the pressure. Of_ course_ Thor will have the throne some day. Nevermind there's no _rule_ it must be the eldest son to inherit. Nevermind that he is rash and impulsive. Nevermind that his solution to any problem is the blunt force of a hammer. He's _Thor_. For all that Loki would surpass his brother in diplomacy and strategy, he cannot engender their realm's love as his brother can. He cannot even engender their father's. Of _course_ it is Thor who will be king.

"Then let all of Asgard rejoice that you are well with mother at your side, for I am far from balanced," Loki replies, trying not to choke on the truth of his own words.

"The day comes sooner than you or I may like," Odin tells him gravely. "And before I fall into the Odinsleep, I would see you better prepared to rule."

"Perhaps if I am not, my brother will be," Loki says. "For you do have _two_ princes and of the two of us, it is he who shows more consideration and forethought. More _balance_."

Odin eyes him carefully before replying.

"There may be two princes, but I have only one throne. I have not the gift of prophecy, but I would still see you readied for the possibility of the crown."

Well… at least he isn't dismissing Loki outright. That's something anyhow, he supposes. But the implication is still heavy and it takes all of Loki's restraint to resist demanding what it is about him that makes him so very easy to cast aside.

"Are my suggestions so outlandish to you, my son?" Odin asks and Loki realizes his silence is uncharacteristic of Thor.

"No," he admits truthfully. "There is wisdom in your words, but that does not mean I shall heed them."

Odin smiles a little at this.

"Yes, I discovered _that_ several centuries ago," he responds. "But I would remind you this - when the time comes that you must settle down and choose yourself a wife, there are certain qualities she must possess. For you will not simply choose yourself a spouse; you will choose your realm a possible future queen. She must be strong and loyal. She must be a leader and an ally. To my eye, there would be no better choice in all the realms than Lady Sif."

Loki nearly trips.

"What?" He asks a little breathlessly, momentarily forgetting he's supposed to be Thor.

"As I said before, she is as fierce a warrior as this realm has ever known and I cannot imagine a more loyal subject of the realm. She would make a fine queen," Odin says, looking amused which is_ grating_ and only serves to further fuel the semi-rational ire starting to boil in Loki's blood.

"And this would be amenable to her, you think?" Loki asks tightly, trying _so hard_ not to picture Sif as Thor's bride and failing.

"There is nothing Lady Sif would not give, I think, to serve her realm," Odin tells him.

A sick feeling floats through Loki's gut as he realizes that is the truth. Loyal Sif, who has no aspirations to the crown, would marry Thor for the sake of the realm if she was told to, regardless of her feelings on the matter. Regardless of her feelings for_ him_, whatever those might be.

"Perhaps," he says. "And yet there is little balance to be found in such a match. We are neither of us diplomats and both far too fond of battle."

_She might better balance Loki_, he almost says but stays his tongue. He is not sure that's an idea he wants to plant in his father's head. Though he's not sure he _doesn't_ want to either, which is a rather startling self-realization on its own.

"You might find these things bind you better to each other," Odin counsels. "And yet, I will not push you on this. You will come to a decision in your own time. I only wished to plant the seed of the idea within your ear."

Loki nods solidly, scarcely trusting himself to speak, for once. So much for his silver tongue.

"For now let us end our wandering, for the winds smell of coming rains and the hour is late. We ought both retire so as to be rested for the feast in the morn," Odin says.

"A feast?" Loki asks.

"Yes. Had you not yet heard?" Odin asks. "Lady Sif and the Warriors Three are victorious. They returned just a bit ago."

"They're back?" Loki asks needlessly as Odin watches him strangely.

He is portraying Thor poorly at the moment, but he _knows_ where Sif is right now and this couldn't be any more messed up if it tried.

"Are you well, Thor?" Odin asks finally.

"I'm fine," Loki replies coldly as thunder rumbles and the clouds roll in. "I just realized there's somewhere I need to be."


	5. Chapter 5

Thor will wonder for a very long time where she got the dagger from, but he certainly will never ask her because none of this will be discussed.

"I assure you nothing nefarious has occurred to warrant the bite of your blade upon my throat," he tells her evenly, her dagger cutting into his skin with every word.

"Your lies are thin, imposter," Sif accuses darkly. "As if I needed further evidence that you are not Loki."

"I would beseige you to lay down your arms, Lady," he implores, but her hand does not waiver.

"And why ought I?" She challenges undaunted.

"Because I do not wish to do you harm," he replies plainly.

The fire of battle flares in her eyes and despite the fact that she is still wet from her bath and clothed only in a bathrobe, she looks primed for war. It's a look Thor is long familiar with and he knows she will strike before he does.

They have met in battle a thousand thousand times. They have sparred together and warred beside each other for near a millenia. He knows her moves as well as he knows his own. But, though she has never held back in their skirmishes - it is not her way - she has also never sought to do him grievous harm. He is not so certain that applies now.

He breaks from her hold, which is not an easy thing, but the stinging sensation on his neck tells him that his escape was not a bloodless one. It is no matter. He has suffered far worse at her hands and may again before this night is through.

"If you think I shall spare you because you wear my lover's face, you are mistaken," she growls at him.

He does not doubt her, but admittedly her choice of words throws him a little.

She takes the offensive, slashing and jabbing at him with fast, hard movements that are borne from the confidence of hundreds of years of victories. The dagger, not even her preferred weapon, is an extension of her arm and she wields it as if she were born with it in hand. But he too has fought and won countless battles and he knows how to evade and strike as well as she.

And yet… and yet this is not his form. He is not used to the shorter frame, the leaner muscles of his brother. He cannot move the same and his strength does not have the heft behind it that he is used to.

He blocks a strike with his forearm, but his arm gives a little under the force of her blow and he lets out a hiss at the feel of the blade's bite slicing against his cheek. The pain is nothing, but he can't help but think Loki's vanity will not tolerate it well if the wound leaves a scar. He uses his momentum to try and sweep Sif's legs out from under her, but even with the wet floor, the shieldmaiden is too aware and too battle hardened to allow that to happen.

His primary goal, he knows, needs to be disarming Sif. For all that Loki was correct before when he said that Lady Sif needs no weapons to dispatch a soul to Valhalla or Helheim, she is infinitely more dangerous with one. His battle-proven moves, however, are failing him. There is simply not enough power in his muscles to strike as he usually would.

Unbidden, the unused magic in his veins sparks forth, tiny balls of green light shooting off at random and exploding against the wall, the bath, Sif's knee. But, try as he might, he cannot control this power as his brother would and unruly power is no advantage in a fight. Besides, to his mind, magic is no fair way to fight. Battle is waged and won with fists and steel, not summoned sparks and duplicitous illusions.

It does, however, offer him a split second of surprise, a rare, momentary distraction for Sif. He knows better than to waste the opportunity.

The move that follows is as inherent to him as breathing, for it is one he has used for hundreds of years. He hits her inner elbow with one hand as he grips her wrist and turns it sharply with the other and kicks the back of her knee. The dagger clatters to the ground and she's collapsed to one knee under the blow of his kick. He expects her to sweep her legs around and knock him down as well, or maybe make a grab for the blade, but he is wrong on both counts.

She's staring at him, paled with disbelief, eyes widened and wary.

"_Thor_?" She asks stunned.

"Your ability to impersonate me remains unsurprisingly flawed," comes Thor's own voice from the doorway and he turns to see his brother with a pinched look on his own face.

"What madness is this?" Sif asks, clearly still on edge as she scrambles back to standing and backs up a few steps.

"I would that we knew," Thor grumbled.

"Loki. What did you do?" Sif demands, eyes narrowing toward Thor's face.

"_Me_?" He asks. "Whyever would you think_ me_ responsible?"

"There has been mischief of a magical nature. Whyever would I_ not_ think you responsible?" She counters.

"She makes a valid point," Thor acknowledges. "But Sif, this is not Loki's doing. Of that much, I am certain."

"Thor…" She says cautiously. "I have no doubt that it_ seems_ as though he is blameless, but to dismiss the likelihood of his involvement would be folly."

"Your faith in me is touching, my lady," Loki says dryly.

"Do not mistake affection for blindness," she snaps. "I know your nature well, Loki."

"Affection? Is that what it is?" He questions.

"Might we please have this conversation when you are once again inhabiting your own body? And preferably without the presence of your brother?" She asks.

"Please," Thor responds gravely. "I have suffered more than enough revelations as to the nature of your relationship today. I would be most grateful to not endure the finer details of it."

Sif actually flushes a bit at that, which is odd and unsettling.

"Come brother," Thor says. "Let us settle in your sitting room while Lady Sif finds more suitable attire."

Sif is far from modest, but frankly Thor has seen her naked more than enough for one day already and a little distance seems a good idea. Loki clearly agrees, as he gives Sif a brief look before turning and heading back the way he came.

"I cannot believe that the two of you…" Thor begins as the brothers reach Loki's sitting room, his voice trailing off abruptly as Thor shakes his head a little.

"I thought you wanted to avoid talk of such things?" Loki asks in a way that clearly indicates _he_ would definitely prefer to avoid talk of such things, anyhow.

"Well, I've no interest in your… lover's spat," Thor elaborates. "But I can scarcely believe such an attachment had formed between my brother and one of my dearest friends and I have failed to notice it."

"Yes. Your observation skills being as keen as they are," Loki says sarcastically in an obvious deflection.

"Are things between you… merely physical?" Thor asks and Loki wonders what his elder brother could have possibly meant in stating he wished to hear nothing of the details if he's going about _this_ line of questioning.

"Yes," Loki says quickly, followed by a highly uncomfortable, "No… Maybe."

"I know you both well," Thor says confidently. "I gather that it is not."

"What? Why? What did she say?" Loki demands, the unsettled look he's sporting settling easily on Thor's features.

"This is a recent development, then," Thor assumes, ignoring Loki's question and obvious discomfort with the topic in general.

"More or less," Loki grumbles, batting in annoyance at the blond locks that keep falling in front of his eyes.

"So how long have-"

"A few decades, all right? Can we move on then?" Loki snaps.

"_Decades_?" Thor asks agape.

"Five or six of them," Loki admits.

"Why brother! You ought be wed by now with the pattering of little feet running in your wake!" Thor exclaims with far, _far_ too wide a grin.

It's unfortunate, really, that Sif dresses swiftly, as she is standing frozen in the doorway at his words. She and Loki are both a bit pale and trying valiantly to avoid eye contact with Thor as well as with each other.

"I'm going to pretend he didn't just say that," Sif announces finally.

"I would be ever-so grateful," Loki says in one fast exhalation of breath.

"But Sif would make a fine princess!" Thor protests earnestly and Loki has never wanted to hit his own face more. "And I am confident that father would be pleased with such a match. He has made quite plain that he is most fond of Lady Sif!"

Yes… Loki is all too aware of his father's approval of Sif. For _Thor_, anyhow. If it's thundering outside, really he can't be held accountable, given the current conversation.

"What use have I for such a title?" She scoffs. "I serve Asgard with a glaive in my hand and battle in my blood, not with court gossip and a babe at my breast."

Loki blinks rapidly at _that_ imagery and some sort of feeling halfway between interested and nauseous settles deep in his gut.

"Asgard can be served in many ways, Sif, and not all of them require a sword in hand," Thor says with a gentle smile that's wholly unsettling on Loki's face.

"Why is this conversation still going on? Can you please stop planning a royal wedding that's _not happening_?" Loki asks, his tone bordering on begging.

Sif watches him for a moment, her expression inscrutable, and she opens her mouth as if to say something to him or ask something of him, but apparently thinks better of it and turns to Thor instead.

"I will always serve Asgard as best I can," Sif says. "And right now that's by helping reverse whatever sorcery has left you trapped in each other's bodies."

"Did you find anything in the library, brother?" Thor asks.

"I couldn't even get past the hordes of fawning fools that appear to accost you at every turn," Loki replies. "The Svensdottir twins say hello, by the way."

Thor flushes horribly at that, the blush standing out in sharp relief against Loki's pale complexion.

"Er… there wasn't… um… that is to say, you didn't…" Thor bumbles.

"Relax," Loki says rolling his eyes. "I've no interest in bedding those simpering fools in my own body and I surely have no interest in doing so in_ yours_. Though… saddling you with a bastard or two _would_ be amusing."

All of the color in Thor's face drains away, but Sif standing nearby just scoffs.

"You are not so cruel as that," she declares.

"Oh, you do have faith in me after all, my lady," he says mockingly.

"As I said before, I know your nature well, Loki," she says with great confidence. "And while I've no doubt that the mischief of it appeals to you greatly, you would not suffer the company of such sycophants as bedmates. The memories of them fawning over you as Thor would torture you for centuries. You would not knowingly endure such suffering that way."

"Perhaps you're right," he says, watching her calculatingly through Thor's eyes. "Perhaps you _do_ know my nature well."

"Perhaps that's why I am still unconvinced of your innocence in this bit of magic," Sif says pointedly, looking between the brothers.

"It's not my fault!" Loki protests.

"For once, he speaks the truth," Thor says in agreement.

"Then what happened, exactly," Sif questions.

"We went searching for the Tyrfing when we were on Alfheim," Thor tells her.

Sif's eyes widen in interest and disbelief as she stares back at him.

"Are you _mad_?" She asks.

"We did not _touch_ it. Obviously," Loki says.

"You found it? You actually found the cursed blade?" Sif asks with all the interest one might expect from the goddess of war regarding a legendary weapon.

"Aye," Thor says, sighing longingly. "And even sheathed, one can see she is a mighty thing. I would that you had seen it too, Sif. You would have appreciated it as few could."

"Where was it?" She asks.

"Er… The treasure room of the Ljósálfar," Thor says sheepishly. "There was a chalice we accidentally knocked over."

"_You_," Loki corrects insistently. "A chalice_ you_ accidentally knocked over. Both of us fumbled to try and save the thing and we both blacked out and awoke in each other's bodies."

"Might I assume that you hadn't gained permission from the Ljósálfar to raid their vaults?" Sif asks. "You are_ princes_, you realize. They likely would have just led you down to see the blade."

Thor looks a little stunned, this thought clearly never having occurred to him, but Loki just grins.

"Where's the fun in that?" he asks.

Sif snorts indelicately in reply.

"I have never heard tale of a cup with such powers," she tells them.

"Nor I," Loki admits. "But it's markings were decidedly not Aesir. It was most definitely elvish."

"Then it's unlikely we will find information regarding it on Asgard," Sif notes.

"I suspect as much as well, yet we must try for we cannot easily return to Alfheim so soon after leaving without questions being raised," Thor says.

"And so we will scour the library," Loki concludes again. "...tomorrow. It has been an exceedingly long day."

"That it has," Thor agrees with a heavy sigh. "We shall reconvene on the 'morrow. Rest, friends… er… not together, _though_, if you please."

Sif throws her dagger at him. He dodges it easily, though, so Thor figures she hasn't really taken offense.


	6. Chapter 6

Notes: So, I'm taking some liberties regarding Mjolnir... I am presuming that until Odin enchanted the hammer the movie, it was not something that no one but Thor himself could pick up. It would, however, be something he was quite possessive of...

* * *

Throughout the years, Loki has woken up in many a disorienting place, but nothing is quite so jarring as opening his eyes to find himself in Thor's bedroom. In Thor's _bed_. But then, he's also in Thor's body at the moment, so when he thinks about it, that's absolutely the strangest place he's woken up in all his 1,100 years.

He _will_ make it to the library today. Come Hel or Ragnarok or Svensdottir twins, he _will_.

He readies himself for the day as quickly as he possibly can, tying Thor's blond hair back because if he has to scour books with it falling in his face all day he is likely to shave it all off out of frustration. Though… thinking about it, that _would_ be amusing, leaving Thor bald. Of course, then who knows what Thor might do to him in retaliation. While Loki loves a good prank, he doesn't particularly relish them being turned back upon himself.

Daylight is scarcely spilling into the room by the time he leaves it, intent to both start and finish this day as quickly as possible, but he doesn't make it further than Thor's sitting room because he finds - to his surprise - that he's not alone.

"Did you _sleep_ in that chair?" He asks, watching Sif as she yawns and stretches.

"Someone has to keep an eye on you," she replies by way of confirmation, reaching for her armor and beginning to strap it on.

"So you're my self-appointed keeper, then?" He asks moodily. "Have you changed your mind about any designs I might have on the Svensdottir twins? Taken it upon yourself to protect whatever might be left of their… virtues?"

"As if you'd do anything that might risk _furthering_ yourself from the crown," she scoffs, looking up at him in disbelief while she buckles a legplate.

Huh… Apparently she _does_ know him.

"And yet… here you are," he points out.

"You bring trouble in your wake, Loki," she says pointedly. "And there is no end to mischief you might cause whilst you inhabit your brother's body."

He tries to look offended and pretends he hadn't just considered shaving Thor's head. Considering their history with hair, Sif might not respond well to that notion.

"How _noble_ of you, Lady Sif," he bites out.

"It's not entirely noble," she allows. "I cannot relish the thought of seeing you beaten to a pulp should you have Thor decline the throne or proposition Volstagg or declare he is giving up war in favor of weaving."

"He would make a terrible weaver," Loki says with a wince, holding up Thor's hands. "Have you seen the size of these fingers? It's no wonder he's such a brute at the dining tables. Can he even hold a fork?"

Privately, however, he wonders if perhaps he's underestimated Sif's usefulness in plots of mischief. For all her decrying his troublemaking, she has some _excellent_ ideas.

"Loki," she says, no small amount of chastisement in her voice.

"Fine," he huffs in annoyance, which no doubt looks quite strange on Thor's face. "I swear to make no move toward abdication or career change or bedding any of the Warriors Three. Does that suffice, my lady?"

It probably ought to bother at least one of them that such a promise _needs_ to be extracted, but it doesn't. Loki is who he is and both of them have long ago accepted that.

"It's a start," she tells him.

"Does that mean you are to remain my shadow, then?" He asks.

"For the time being," she states, as if she's waiting for him to challenge her.

"I suppose it would be unusual if you _weren't_ trailing around after Thor," he muses, to which she gives him a rather vicious glare.

"I will not have this argument with you again and I most certainly won't have it with you while you are wearing Thor's face," she grits out.

"Fine," he says, realizing he doesn't actually want to have this fight with her right now anyhow, and going to run his hands through his hair only to find it's tied back and blond and annoying and Thor's. "Let us see if we can't resolve how to undo this whole mess, then."

"Actually…" Sif says. "You are sparring with Hogun this morning."

"I'm sorry, _what_?" Loki blinks.

"Thor promised him before you left for Alfheim," Sif tells him.

"I will make some excuse," he resolves.

"Yes, because Thor is so well known for declining a fight," Sif points out.

"Sif... I don't have my magic," he admits with no small amount of embarrassment. "How am I to fight?"

"With Mjolnir, I'd suggest," she tells him.

Loki stops at that. Thor's precious hammer. He is so very possessive of it. So far as Loki knows, no one else has wielded it since it fell into Thor's hands. It might not be shaving Thor's head or taking up weaving, but fighting with Thor's hammer is its own kind of mischief. And anyhow, Thor has his magic right now so it seems only fair.

"You're relishing this idea entirely too much," she declares, looking faintly amused. "Do try and remember you have Thor's muscles. We don't want Hogun to end up in Eir's care or missing any limbs."

Oh yes… this is a fantastic idea. Loki cannot help but relish the notion of fighting one of the Warriors Three and having the upper hand, for once.

"Not to worry, Sif," he smiles a little too broadly, crossing the room to where Mjolnir is propped up against a potted plant and grabbing its handle triumphantly. "Come on, then. We oughtn't keep Hogun waiting. It might sully Thor's reputation, after all."

She rolls her eyes but says nothing as they head toward the door. As it turns out, however, potential tardiness might have had less of an effect on Thor's reputation than leaving just then does.

They are not alone when they exit into the hall.

Fandral just so happens to be walking past Thor's door at exactly the right time to see 'Thor' and Sif leaving the prince's rooms scarcely after dawn. There's absolutely no way that the most debauched of the Warriors Three interprets this as anything other than a torrid affair.

"Prince Thor… Lady Sif… What an… unexpected pleasure running into you both so early this morning," Fandral says with a too-broad grin and a vibrant twinkle to his eye.

"Not so unexpected, surely," Sif says quickly. "Thor and Hogun are to spar shortly. I've just come to remind him their appointment."

"Of course… of course," says Fandral nodding, clearly not believing a word of it.

Sif shakes her head at him before passing him by with a sure stride and perfect posture. Fandral looks toward Loki with raised eyebrows clearly asking a question he's not about to voice within Sif's earshot. Loki, being exactly the troublemaker Sif asserted him to be, winks at Fandral by way of reply.

Fandral smiles with entirely too much delight.

Loki thinks Sif will kill him later, possibly, when rumors abound. And he will hate it when whispers about her and Thor make their way back to his ears. But, in some ways, implying her involvement with the elder prince works solidly to his own benefit. It throws off suspicions that might be cast upon them otherwise and - if he's very, very lucky - possibly it will force a little more distance between herself and Thor.

_That_ would most certainly be a welcome thing. For as much as he grudgingly loves his elder brother and holds an irrational fondness for Sif, there is a sickness that builds in his gut as the two of them fight and laugh and feast side-by-side decade after decade.

Thor's absurdly long legs easily make up the distance between himself and Sif in short order and Fandral follows suit, the three of them heading briskly toward the training yard. Fandral looks like he has entirely too many things he wants to say, but the rakish swordsman wisely bites his own tongue in Sif's presence, proving he has more sense than Loki has ever presumed.

The night's storm has long since cleared and the ground is only scarcely damp, Loki notes as they make their way outdoors. Hogun and Volstagg are already there, he finds. The latter is gesturing broadly and loudly proclaiming _something_ with entirely too much mirth. But Hogun… Hogun is silent. Unsurprisingly.

Loki has always been wary of the quiet warrior. Centuries have taught him that those who speak sparingly do so with greater precision and study their surroundings and their companions more closely. For all of Fandral's annoying boasts and gossip and Volstagg's exaggerated tales and sickeningly friendly nature, he will take them over Hogun's watchful contemplations every time.

He enjoys his tricks and his secrets far too much to enjoy Hogun's company.

"My friend!" He calls loudly, as Thor might. "Has your mace not had its fill of blood? Tale says you've single-handedly decimated the mountain troll population."

"Hardly single-handedly," Fandral mutters, sounding a little hurt.

"Might as well have been," Sif gripes, obviously still sore about being denied a kill.

"As always, my weapon is at my prince's command," Hogun says with a little smile.

"Then raise it now against me in contest," Loki orders.

As it turns out, Thor's brawn with Loki's brain makes for a rather overwhelming opponent.

He might not have the power of his magic at his disposal, but Loki finds he truly doesn't need it. Not this time. Not against Hogun and not with Thor's body at his command. The sheer power behind his swing of the mighty Mjolnir is astounding. Coupled with the craftier moves he calls his own, he is a force to be reckoned with.

The battle, such as it is, is a foregone conclusion from the moment it begins. For all that Hogun is a fine warrior, he has neither Thor's strength, nor Loki's mind, nor the power of Mjolnir at his disposal.

It takes mere minutes before Hogun is well and truly beaten and Loki's grin at his triumph is perhaps the most genuine one he has ever worn.

"Do you yield?" He asks, a lone lightning bolt shooting down from the sky and striking the ground just a few feet away from Hogun as a sort of exclamation point.

He's sure he hears Sif huff at his display of power from somewhere behind him, but he can't be bothered to care.

"Aye," Hogun replies, wiping blood from his lips. "Today finds you in fine form and a rare mood. It would be a fool who would not yield to you today, my lord."

Loki's grin would split Thor's face with his smile if it could.

"Are there any other fools here today, then?" He asks, looking around at his other companions.

"I make it a point not to bleed before breakfast," Volstagg says.

"Hogun's bled enough for all of us, I think," Fandral points out.

"I slept poorly, my lord. I fear I'd be a poor contest today," Sif says and Fandral makes a choking noise.

"Slept poorly?" Volstagg questions as Sif makes her way over toward Hogun to help him up.

"In _Prince Thor's rooms_!" Fandral tells his friend in a hushed voice that Loki can scarcely hear.

It is with total and complete amusement that Loki hears his own voice make a strangled noise that can _only_ mean that Thor has just heard Fandral and Volstagg. This day is fast becoming his favorite ever.

He turns, expecting to see his own face mirrored back at him, and he _does_… sort of.

"What's happened to your _hair?_" Fandral asks, his tone exactly as horrified as Loki actually feels.

"I… thought I'd try something different," Thor says, self-consciously running his hand through Loki's unruly curls.

"I… I… I take my leave of you, my friends," Loki says, eyes fixed on Thor and the ridiculous hair but still spying Sif biting her lip to keep from laughing out of the corner of his eyes. "_Brother_… if I could have a word."

Loki grabs Thor by the arm hard enough that he's sure its going to bruise and he's actually annoyed by realizing that he's bruising _himself_, but he still can't quite get himself to loosen his grip. Behind him, Sif hands Hogun off to the other two warriors and hurries to follow in the brothers' wake.

"Have you lost your mind?" Loki hisses.

"I looked through all of the books of spells in your room!" Thor protests. "I could find nothing to tame this beast you call hair. And _give me my hammer_!"

"Clearly you didn't check my bathroom for _hair gel_," Loki grits out, handing over Mjolnir.

"I… did not think of that…" Thor admits. "And yet, my misstep pales in comparison to words uttered by our friends just moments ago."

"I slept in a chair in your sitting room to ensure a negligible amount of mischief was done in your name," Sif says, finally catching up. "Unfortunately, Fandral happened by as I was leaving which will certainly get _those_ rumors going again. May I touch the hair?"

"Certainly," says Thor.

"No!" Protests Loki at the same time.

Unsurprisingly, she listens to Thor and reaches up to twist a lock of the curls between her fingers.

"I like it," she smiles a little, looking toward Loki as she speaks. "You ought leave it curly sometimes. It's quite soft."

"It makes me look like a toddler," Loki says indignantly. "All cherubic and ridiculous."

"No one who knows you would ever mistake you for cherubic," Sif points out, her fingers still playing with the locks of Loki's hair. "I think it's rather attractive, actually."

"I'd listen to her, brother," Thor counsels. "There's something to be said for the feel of a woman's fingers in your hair and if she likes it this way, it can only be to your benefit."

Loki sputters something unintelligible before regaining a sense of control.

"With all of our concerns right now, the two of you choose to focus on _my hair_?" He asks in exasperation.

"He has a point with that," Sif admits.

"He does," Thor agrees.

"We need to fix this. _Now_," Loki insists. "The three of us are going to the library and we will stay there until we've exhausted every resource at Asgard's disposal. Agreed?"

His companions nod and all three of them take off in the direction of the library. It's only a few turns of the corner, though, before they all stop in their tracks.

Odin has been fooled, as have the Warriors Three, and Sif is their accomplice at this point. However… there is another hurdle they all seem to have forgotten.

And they have just encountered her.

"Mother…" Thor says as Frigga stops and eyes them warily.

All three of them shuffle nervously like children under her gaze.

"Loki Odinson," she finally pronounces looking straight at him, not fooled for a moment by the mask of Thor's face. "What have you done?"


	7. Chapter 7

First off, I am so very sorry that this has taken a ridiculously long time to finish and I'm incredibly grateful to anyone who still has an interest in it. Thank you again to everyone who has shown their support for this little fic. It means a tremendous amount to me and has kept me going. While this is the last chapter in this fic, I will certainly be writing more both in MCU Avengers-verse and for Loki/Sif as I continue my trope bingo challenge.

* * *

As it turns out, it doesn't matter if the library has information regarding their mysterious cup, because their mother is exactly as knowledgeable about it as she is insightful about _them_. She's also wise enough to realize that the hallway is a spectacularly terrible place to have a conversation that one might not want to be overheard.

"Not here," she'd told them crisply, immediately following her question to Loki.

She hadn't told them to follow her. She hadn't needed to. All three of them had trailed after her to her private sitting room in total silence. If it was somewhat reminiscent to the brothers, sheepishly squirming under Frigga's knowing gaze and awaiting punishment for some bit of mischief or tussle, well… that was probably Frigga's intent.

"Well?" She'd prompted the moment she'd secured the door behind them. "How is it that my sons have managed to switch their _souls, _Loki?"

"Why does everyone assume it's my doing?" Loki had asked petulantly.

Frigga had not indulged him with an answer, instead leveling him with a withering look that even Loki winced at. The story had tumbled from his lips rather quickly after that.

Now, with most of the tale selectively confessed - none of them are particularly keen to address why Sif is involved - Frigga seems less angry, perhaps, but substantially more exasperated.

"The cup," she begins, "I presume it to be thin and made of a translucent deep blue stone with etchings that look as though they might nearly go the whole way through the chalice?"

"You know it!" Thor exclaims with jubilance that frankly looks a bit silly on Loki's face.

"I should," Frigga tells them. "I watched my father craft it."

"He _made_ it?" Thor asks. "Whatever for?"

"More importantly, did he create a way to reverse its effects?" Loki asks.

"It is a chalice, my sons," Frigga says, eyeing both of them as she jots something down on some parchment before sealing it with her stamp in wax. "How do you _think_ its effects might be undone?"

Loki scoffs and shakes his head a little bit at his mother's words.

"We drink from it," he says, looking a little miffed that this idea hadn't occurred to him sooner.

"You drink from it," she confirms with a slight nod of her head.

"But how are we to obtain the chalice?" Thor puzzles. "For it resides beyond our reach on Alfheim and I cannot imagine the elves would simply hand it over with no explanation."

"Think you they would deny the Aesir queen the right to borrow her own father's creation?" Frigga asks.

"They would not," Loki says with great certainty.

"In truth, I should like very much to see it again," Frigga admits, a small smile gracing her lips and a far-away look living in her eyes. "Some of my earliest memories are of my father fashioning that cup as I sat at his feet with all of the impatience of youth, begging him to take me riding or swimming instead.

"'Tell me, ástin mín,' he said to me. 'How can the Dökkálfar and the Ljósálfar begin to find peace if they cannot even learn to see each other's points of views?" She recalls.

"He sought to unite the _elves_?" Loki questions skeptically. "His time would have been better served spending it as you had wanted. The Dark Elves were savage beasts."

"Be not so disbelieving, my son," Frigga smiles. "If you believe the worst in someone, they will prove you right more often than not. Yet, sometimes, faith and compassion can bring about the most miraculous of changes."

"But it didn't work," Thor says. "King Bor destroyed the dark elf menace for the good of the realms."

"It did work, actually… for a time," Frigga replies. "But that is a complicated tale for another time and we have more pressing issues at the moment. Lady Sif, might I impose upon you to deliver this missive to the Alfheim court with the greatest expediency? If all goes as I expect, I would hope for you to return with the cup in hand by this eve."

"I would be most honored, my queen," Sif says, taking the paper with a bow of her head.

She leaves immediately thereafter, but not without her eyes flicking toward the princes.

"Tell me," Frigga says to her sons as the door shuts behind Sif. "How did Lady Sif come to know of your situation?"

"Er… she recognized that we were not our true selves," Thor says shiftily.

"And however did she do _that_?" Frigga asks them.

"Fighting styles," Loki interjects before Thor can speak.

"Yes," Thor agrees, looking wholly relieved that Loki has stepped in.

"...Of course," Frigga muses in a tone that neither of her sons are fond of. "She is an observant woman and a true and loyal friend to the both of you."

If she focuses her gaze wholly on Loki as she speaks, that's just one more thing that neither of the princes will choose to acknowledge later.

* * *

Sif returns with the chalice before supper and delivers it directly to Frigga's hands. The queen looks at the cup with such reminiscence and affection that Sif dips her head in respect rather than watch.

"I thank you, Lady Sif," Frigga says after a moment, placing a hand on the shield maiden's shoulder. "Both on my own behalf and on behalf of my sons."

"It is my honor, as always, my queen," Sif replies.

"I'm certain you are most tired from your travels today, but if you would not mind, might I ask you to send both of my sons to me before you retire for the day?" Frigga asks her.

"Of course," Sif agrees readily.

In all honesty, she is more restless than she is tired. The queen's missive certainly sped her through the process of the Alfheim court's formalities for receiving visitors, but there was still a fair bit of standing around waiting and inaction has never sat well with Sif. Regardless of that, however, Sif cannot imagine ever being tired enough to refuse a task bid her by the queen.

She seeks out Thor first. It's unintentional, really. Her feet just steer themselves towards Loki's rooms on their own, which is not surprising but is something she's going to try not to think about too closely. Thor is there, hair still untamed, and her lips twitch in amusement and thinly veiled affection at the sight.

"You have returned victorious, then!" Thor booms immediately upon opening Loki's door, ruining any possible illusion of him being Loki.

"It was hardly an epic quest worthy of song, Thor," she says disbelievingly.

"That all depends on how you tell it," Thor declares with a grin.

He's not entirely wrong. Fandral's stories alone are proof enough of that.

"And yet... " Thor continues, following her out of the room into the empty hall, "I much appreciate your discretion in refraining from sharing this particular tale."

"Believe me," she replies, "I have a greater want for discretion in all this than you do. You needn't worry about the looseness of my tongue."

"That is…" Thor begins before cutting himself off. "I will, of course, respect your want for privacy, but I must admit I wonder at it."

Sif huffs a little at his words. She ought have expected something like this, really. Ought have, but hadn't. Thor is refreshingly open. It's one of the things she adores about her friend, but he can't seem to understand why others don't live their lives in the same way - laid bare for all to see. There is no way in which he and Loki are more opposite than this.

"Court gossip is kinder to you than to I… or to Loki," Sif says, highlighting one of the many reasons she'd rather her relationship with Loki remain unknown. "And besides, I would scarcely have the words to define it anyhow."

"Hmm," Thor says pensively, brow furrowed as he nods. "And yet… after all this time, mayhap it would be to your benefit to at least sort that bit out between yourselves."

Her feet stop abruptly and she stares at him a bit agape.

"Truthfully, Thor? You think to offer me _relationship_ advice?" She asks bewildered.

"I would not be so bold as that," Thor assures her. "I merely… I worry for you and for my brother, that perhaps you each have separate expectations for this attachment. Loki displays little, but it is evident to me that he feels much."

"And you worry that I do not," Sif says.

It's not a question.

"I admit… I do not know," Thor says plainly.

"What would you bid me say, Thor?" She demands. "Do you need to hear me say I love him?"

"Sif, I would not presume-" Thor begins.

"I do," she interrupts, chin held high but no small amount of vulnerability in her voice. "I love him madly. In truth perhaps that makes me mad, for he is not an easy man to love."

The words have sat upon her lips unsaid for so long that they tumble easily, desperate to be heard at last, by Loki's ears if not by Loki himself. And, oh, it is a strange thing to finally speak such things to Loki's face but have her admission go unheard by her lover. A look of deep sympathy softens Loki's eyes and if ever Sif had seriously entertained a notion of saying this to Loki himself, that look alone would have killed it. She cannot bear the pity worn upon his face. Not over this.

"You've not told him this in all the decades you've been together?" Thor asks too gently.

"How think you he would take such a confession?" Sif questions in challenge.

"I should think any man would be happy to hear such a thing from you. And Loki has more reason than most to desire it," Thor says kindly.

"Perhaps," Sif acknowledges. "If he believed me."

"You think he would not?" Thor asks in surprise.

"Thor… he is _Loki_," Sif sighs. "When does he take anything at face value?"

"He is suspicious by nature," Thor agrees. "But surely with all the history between you, he would have faith in such a notion."

His words are not quite a question but there is a lack of certainty in his voice that Sif feels in her bones.

"Loki believes best what he thinks himself to have discovered," Sif asserts. "I cannot tell him. But I will continue to show him. And, perhaps, one day he will see it for himself."

"I love my brother dearly, but I wonder if you are not better than he deserves," Thor says.

Sif snorts at that.

"On the contrary, my friend," she smiles, grateful for the lightness their conversation has twisted toward. "I am combative and hardheaded and bold to an unseemly degree. There are many who would argue I am _precisely_ the sort of person Loki deserves."

Thor grins broadly.

"Well… when you put it _that_ way…"

Sif grins back.

"Your mother awaits you, my friend," Sif tells him, still smiling. "I shall seek out Loki and send him in your wake. When next I see you, I hope for you to be in your own form."

"On that, dear friend, we most assuredly agree," he replies, giving a little bow of Loki's head and turning down the hall toward his mother's rooms.

In the end, it is far simpler than either Thor or Loki would have presumed to end this entire charade. With their grandfather's cup full of water from the Well of Urðr - something Loki seems positively stunned that their mother has readily on hand - it takes but two sips and a few moments of unconsciousness before Thor finds errant strands of blond hair once again impeding his vision.

Thank the Norns.

The itch of magic is gone from beneath his skin and the heat no longer bothers him so. And yet… and yet there is much of the experience that has stuck with him. This is, of course, the very point of the chalice. It has done its job well.

Immediately upon awakening, Loki conjures dozens of duplicates of himself. For the first time, Thor recognizes the look of relief that settles lightly upon his brother's face as the build-up of magic bleeds off of him.

"Was conjuring a ball of light _really_ all that difficult?" Loki drawls as the duplicates dissolve around him.

"Anything is difficult when attempted for the first time," Thor reminds him, earning a small smile of agreement from their mother. "You've said for many a century that you are a master of the magical arts. Until this day, I had not known the truth of that."

Loki watches him warily, obviously waiting for some qualifying statement that waters down the compliment, but Thor gives none. Somehow this serves to make Loki all the more unsettled.

"I have much to do," Loki says after a long moment of silence. "Mother, you have my thanks."

"Of course," Frigga demures. "Do pass along my gratitude to Lady Sif… when next you see her."

Thor covers a chuckle with a coughing fit and Loki can't seem to decide which of them he wants more to glare at. In the end, he seems to settle for darting his narrowed eyes between them before nodding sharply and turning to leave the two of them alone in each other's company.

"You've learned much these past two days, my son," Frigga says knowingly, staring after the empty space where Loki had stood before turning to Thor.

"Aye," Thor agrees. "I must admit, in some ways I see Loki now in a new light."

"And he you, I am certain," Frigga smiles.

Thor is less sure of this. There is little for Loki to discover about him that he does not already know.

"Perhaps," he allows agreeably.

"For all the folly in your actions that led you to this little adventure, I cannot help but think it might foster a deeper, richer friendship between you," Frigga tells Thor watchfully. "And ensure a… better understanding of how your actions might affect each other."

Thor raises an eyebrow at his mother, for her comment lacks all of her usual subtlety.

"Indeed," says Thor. "And on that note, might you know where I can find father? I should like to provide him with a more decisive answer to his proposal."

He had never been of a mind to marry Sif, but he would not have discounted it so entirely were it not for Loki's now-obvious attachment to her. Perhaps Loki and Sif will remain stubbornly unclear with each other or perhaps they will end whatever semblance of a relationship they have, but - for love of them both - Thor will have no hand in.

Frigga's smile is broad and full of pride. She touches her palm to her elder son's cheek with motherly affection.

"I am glad at this choice," Frigga tells him. "And yet, your father was right in one aspect. She would make a mighty queen."

"Aye," Thor agrees. "She would… given the right king."

"Given the right king," Frigga echoes with a nod.

Thor might be the right king for Asgard one day - he believes he will with all of his conviction - and yet, he will never be the right king for Sif. Not as queen. And it is past time to end such notions in his father's mind.

* * *

She falls beside him on the bed, bare and breath heaving and skin slick with sweat. Undoubtedly, her pulse is slowly edging toward normal, as his still is. She is languorous, stretched out against his cool ivory sheets, at ease in a way he rarely sees her in public.

He is immeasurably glad to be back in his own body.

"Mmm," she hums, a contented little noise as she turns on her side to face him and lets her fingers drag through his still-untamed hair.

He did not leave it curly for her. He _did not_. He… merely hadn't had the time to rectify his brother's mistreatment of his locks. That is all.

That's his story and he's sticking to it.

"I _am_ glad to have you back," Sif says.

"Had I gone somewhere?" Loki asks, trying not to groan or whimper or anything else wholly embarrassing but - by Yggdrasil - Thor was right about the feel of her fingers in his hair.

If he dips his head a little toward her to let her more easily drag her nails against his scalp, he will never admit to it.

"You had split in two and left me wanting for the whole," she tells him. "For I cannot imagine being satisfied having but half of you."

He cannot help but grin at her words, triumph or affection or _something_ pulsing in his veins. It is so rare that he is chosen over Thor. For anything. And to think she prefers himself in his own body over either his mind in Thor's or Thor's mind in his… that is no small thing. Not to Loki.

"Well… far be it from me to leave the lady unsatisfied," he responds, tracing a finger lightly down her side and delighting at the shudder that follows in its wake.

"No such worries _now_, my prince," she says, breath catching as his thumb traces the inner curve of her hipbone.

"And yet, as prince, it is my obligation to see to the needs of my people, is it not?" He asks, dipping his mouth to nip at the skin of her collarbone.

"I… _ah_… I believe it is," she responds unevenly, draping a leg over his hip and pulling his body closer to hers.

"So, perhaps I owe some additional recompense for my earlier inattention to your needs," he speaks against her skin as his lips work their way downward to her breast.

"That was understandably out of your control, my prince, and I would not have wanted the attentions of half of you. But… who am I to refuse a favour from the crown?" She asks with something between a laugh and a moan.

He rolls atop her, settling himself between her thighs and dipping down to kiss her lips. The press of his mouth to hers is long and cherishing. When he finally pulls back he takes in the dazed, happy look in her eyes as he brushes a stray lock of dark hair away from her cheek.

"Who, indeed," he echoes softly.

* * *

It is scarcely two weeks before their next adventure begins. Goblins on Vanaheim have been ransacking some of the smaller villages, stealing and slaughtering their way through the Vanir old country. It is an honorable and pleasurable quest to seek out such beasts and bring the villages back to their normal peaceful state.

Loki, Thor, Sif and the Warriors Three set out together on their campaign for honor and glory and recovering of stolen riches. Thor's mostly in it for the songs they will sing of his victory; Loki's mostly in it for the magical relics they might recover. But, regardless of that, it's an honorable quest and Odin has happily bid them forth to defend the Vanir.

And, anyhow, it feels good for things to finally be back to normal.

The goblins are easy enough to find, having built themselves a series of tunnels and caves through the nearby mountainside. They are brutal things, small with sharp, poisonous teeth and long razor-like claws. But they are no match for Asgard's finest and it takes but a few hours for the menace to be exterminated.

"Are there no more?" Sif asks with a huff of frustration as she yanks her glaive free of the last goblin's corpse.

"Has the battle in your blood not yet been sated, my lady?" Loki smirks toward her. "Need you more adventure? Perhaps you ought find a healthier outlet for such aggressions."

Fandral and Volstagg shake their heads a bit at Loki's baiting but Thor shudders a little because after their last adventure he's _pretty_ sure this is their version of foreplay and he'd really rather not know that.

"Tempting her into a duel here, while likely entertaining, is perhaps not the best idea," Fandral counsels Loki. "And besides! There is treasure to be found!"

Sif stares at Loki hard enough and long enough that he's certain securing the stolen relics and making their way back to camp will be _infinitely_ more entertaining than a duel.

"Goblins would keep their loot in the lowest point of their tunnels," Loki says by way of agreement.

"Then downward we shall go!" Volstagg declares, thumping Hogun on the back and ducking to make his way through the tunnels.

"They shall know if you continue to be so obvious," Thor says in a hushed voice to Loki as the two of them keep toward the back of their small group.

"Sixty years of such comments and they've not noticed before," Loki reminds him, both of them hunched awkwardly to fit through the goblin tunnels.

Thor wonders at that. Have they always been so blatant? Has he truly missed the underlying current of their banter for decades? It seems so obvious to him now.

"Look at all of this!" Fandral's voice rings out and Thor shakes off his thoughts to look around the small cavern they've tumbled into.

It is clear that the goblins have been stashing their treasures here for many years. Forever craving anything shiny, the goblins have piles of coin and jewelry and ceremonial relics that far surpass Thor's expectations.

"What a tremendous find," Fandral says with a bit of awe as he reaches toward the pile.

But it is not jewelry or coin he reaches towards. No, it is a finely crafted, paper-thin chalice with detailed etchings. For a long moment, Thor's breath catches in his throat and his eyes go wide.

"No!" He cries, his voice in concert with Sif and Loki's as Fandral's fingers wrap around the stem of the cup and his eyes roll back up into his head.

Hogun and Volstagg crouch worriedly next to their friend, each of them touching his unconscious form before immediately passing out themselves. Thor sighs and looks to Sif who is rolling her eyes and Loki who seems entirely too amused given the circumstances.

"Well, Sif," says Loki with a clever smile. "You wanted more adventure."

"And yet, this is not quite what I had in mind," she counters.

"Perhaps, in the future, you ought be more specific," Loki says, staring down at the prone forms of the Warriors Three.

"What are we to do with them?" Sif questions, eyeing the warriors.

"Leave them?" Loki suggests, earning malice-filled glares. "A jest… merely a jest."

"Let us wait for them to awaken and see what this chalice has done, for whilst its maker is clearly familiar it may yet prove to have unique properties," Thor says.

"True," Loki admits. "T'would be a pity, though. I'd rather like to see Fandral deal with Volstagg's beard and Volstagg's appetite in Hogun's body."

"Of course you would find this amusing," Sif berates him lightly. "Now that its not happening to _you_."

"I've no idea what you're talking about, Sif," Loki says loftily. "For surely such a fate would never befall a prince of Asgard. Right, Thor?"

"My brother speaks the truth, Lady Sif," Thor nods. "We know not of what you speak and we shall deny such an experience until our dying days."

"Of course you will."


End file.
